Preface - kmutt

KMUTT Annual Research

KMUTT Annual Research Abstracts 2005 Starch Technology (BioThailand 2005), November 4-5, 2005, Queen Sirikit National Convention Center, Bangkok, Thailand, p. 352 The pasting properties of rice starch following storage of the grain for up to 7 months were investigated. The significant difference of the color of the milled rice was shown in the rice during storage. The data confirm that viscograms from samples stored at 25°C and 37 °C provide a valid comparison of the effects of aging on pasting behaviour. It was found that gel consistency of rice starch decreased with time of storage from 95.33 to 82.33 and 95.33 to 69.67 mm for rice storage at 25 °C and 37 °C; respectively, and gel consistency value of the rice stored at 25 °C were higher than that of the rice stored at 37 °C. Setback and final viscosity of rice starch pastes generally increased with both temperature and time of storage. Fresh starch paste exhibited lower peak viscosity (Vp). Vp of rice starch of the rice stored at both temperature increased after storage after that peak viscosity pastes slowly gradually increased. However, peak viscosity (Vp) of rice starch of rice stored at 25°C increased from 195.97 to 278.88 RVU with time of storage and higher than that of rice stored at 37°C increasing from 195.97 to 309.79 RVU. Pasting temperature ranged from 78.39 to 71.17°C and 78.39 to 69.89°C for rice stored at 25°C and 37°C, respectively. Storage led to a gel consistency value in milled rice and the decline was greater at 37°C than at 25 °C storage. This study suggested relationship between pasting characteristics and storage time of milled rice cv. Khaw DokMali. Thus it might be indicated that temperature appears as a key comnonent in the aging process. IC-267 PHYSICAL AND PASTING PROPERTIES OF BROWN RICE STARCH DURING STORAGE Lamul Wiset, Songsin Photchanachai, Jirasak Kongkiattikajorn Starch Update 2005 : The 3 rd Conference on Starch Technology (BioThailand 2005), November 4-5, 2005, Queen Sirikit National Convention Center, Bangkok, Thailand, p. 350 In this study, the lipid components, pasting properties and the color of brown rice cv. Khaw DokMali during storage were investigated. Storage produced changes in the 169 total free fatty acid, RVA pasting properties and the color of the brown rice as a varietal, time and temperature dependent phenomenon. The significant difference between the color of the brown rice, total free fatty acid contents and the pasting behaviour of brown rice starch was shown in the rice stored at 25°C and 37°C. There was the negative correlation between color of brown rice and total free fatty acid contents in the both stored rice. For relationship between the color of the brown rice and pasting properties, there was the positive correlation between the color of brown rice and total peak viscosity of storage rice at 25°C but there was the negative correlation between the storage rice at 37°C. As for the scatter diagram of peak viscosity and total free fatty acid contents of the storage rice represents the linear regression. The results indicated the correlation between physical, physiochemical characteristics and free fatty acid contents of brown rice. This study identifies the temperature and time as critical control points in the changes of free fatty acid contents, physical and physicochemical properties of the post harvest rice. IC-268 QUALITY ALTERATIONS OF SWEET BASIL STORED IN MAP AT CHILLING TEMPERATURES Chalermchai Wongs-Aree, Chaunpis Jirapong, Sompoch Noichinda, Sirichai Kanlayanarat APEC Symposium on Assuring Quality and Safety of Fresh Produce, August 1-3, 2005, Radisson Hotel, Bangkok, Thailand Sweet basil (Ocimum basilicum L.) is a tender herbaceous annual plant growing around tropical zones. As a useful culinary herb, the basil leaves contain unique aromas and volatile oils, contributed as additional flavour in many foods and drinks. A crucial problem of exported sweet basil is accelerated shelf life due to water loss. To prolong the storage life, polyethylene (PE) bag and various low temperatures were selected to study. Sweet basil branches at 80 g average were sealed in a 12 µm PE bag (20 x 45 cm in dimension) with 4 perforated holes (0.7 cm in diameter) and stored at 4, 7, 10 and 13°C with 86±3% RH in cold rooms. Water loss and chilling injury symptoms reveal to be major indicants, limiting the storage life. Thirteen degree Celsius was the optimum storage temperature that acceptable quality of stored basil was extended to 15 days. After 9 days, International Conference

170 sweet basil stored 4°C showed severe chilling injury symptoms. Moreover, leaf dropping, found increasingly between the storage proceeded, has emerged to be another concern in this MA storage. Colour a values (Hunter scale) inclined rapidly in basil leaves stored at 4°C. However, total chlorophylls in leaves measured in SPAD unit were not different between treatments. IC-269 LOW O 2 AFFECTS ON QUALITY OF MANGO (Mangifera indica CV. NAMDOKMAI) AT CHILLING TEMPERATURE Ratanavan Jansasithorn, Chalermchai Wongs-Aree, Varit Srilaong, Sirichai Kanlayanarat APEC Symposium on Assuring Quality and Safety of Fresh Produce, August 1-3, 2005, Radisson Hotel, Bangkok, Thailand Mango fruits cv. 'Namdokmai' at the mature green stage were stored at 8°C in air (control) or in 3% or 5% O 2 . Both low O 2 treatments had comparable inhibitory effect on weight loss and respiration rate. After 30 days storage, the fruits lost only less than 2% of their original weight whereas in air, weight loss was more than 15%. Respiratory inhibition by low O 2 was also very remarkable as the rates never increased to levels similar to that in air throughout the storage period. Pulp softening was more effectively inhibited by 3% O 2 than 5% O 2 . However, this did not translate into a corresponding increase in shelf life. AH low O 2 - stored fruits lasted in storage by 10 days longer than that in air. IC-270 HIGH CO 2 AFFECTS ON QUALITY OF MANGO (Mangifera indica CV. NAMDOKMAI) AT CHILLING TEMPERATURE Ratanavan Jansasithorn, Chalermchai Wongs-Aree, Varit Srilaong, Sirichai Kanlayanarat APEC Symposium on Assuring Quality and Safety of Fresh Produce, August 1-3, 2005, Radisson Hotel, Bangkok, Thailand Mango fruits cv. 'Namdokmai' at the mature green stage were stored at 8°C in air (control) or in 3, 5, 10 or 15% CO 2 . High CO 2 regardless of concentration remarkably decreased weight loss and slowed down softening. Respiration rate also decreased with KMUTT Annual Research Abstracts 2005 high CO 2 treatment at 3-5%. At 10-15% CO 2 , respiration rate was much higher than that in air and the fruit developed surface discoloration, pitting and off-odor resulting to a shorter shelf life than in air. In contrast, 3-5% CO 2 increased fruit shelf life by about 10 days longer than that in air. IC-271 IMPROVEMENT OF GREEN COLOUR PRESERVATION IN GA 3 TREATED LIME USING MAP AND CHITOSAN COATING Penvipa Vasanasong, Apiradee Uthairatanakij, Chalermchai Wongs-Aree, Sirichai Kanlayanarat APEC Symposium on Assuring Quality and Safety of Fresh Produce, August 1-3, 2005, Radisson Hotel, Bangkok, Thailand ‘Paan’ lime (Citrus anrantifolia Swingle L.) containing distinguished flavour is one of popular varieties in Thailand. A previous study found that green peel colour was decently maintained by dipping in gibberellic acid (GA 3 ) before storage. In this study, 200 ppm GA 3 treated lime were coated with 0.5 and 1.0 % (w/v) chitosan and kept on a foam-tray wrapped with LLDPE shrink film and then stored at 13°C (92±2% RH in the room). Levels of internal O 2 were not less than 18% while internal CO 2 concentrations were raised by 4% in lime fruit under MA conditions during storage. MAP showed a great effect on a reduction of weight loss compared to use of chitosan coating. However GA 3 combined with chitosan coating performed a synergic action on chlorophyll preservation in lime peel, related to slowness of L values increasing. Titratable acids of all treatments increased modestly after 50 days while ascorbic acid increased after storage and reduced sharply after 50 days. IC-272 INHIBITION OF PERICARP BROWNING IN LITCHI CV. CHUKRAPUD BY CONCENTRATION OF CHITOSAN COATING Sakorn Nuntawichai, Apiradee Uthairatanakij, Chalermchai Wongs-Aree, Varit Srilaong, Sirichai Kanlayanarat APEC Symposium on Assuring Quality and Safety of Fresh Produce, August 1-3, 2005, Radisson Hotel, Bangkok, Thailand Litchi pericarp is highly perishable turning brown quickly within 2-3 days after International Conference